What troubleshooting tips can help when filing a 90-day address report online in Thailand?

I just filed my 90 day address report online and I experienced something interesting. When I tried to submit the first page I was getting the error that tells you nothing useful. That was strange as I have filed online successfully the past two times. So, I was scratching my head trying to figure out what could be wrong. I was in the acceptable time window to apply so it seemed a mystery. Then, I had an idea. On the "Arrived in Thailand(Date)" field I had manually entered the date. For some reason I decided to try using the little calendar tool to select the date instead. Submitted again and, voila, success. For what it's worth, I had tried unsuccessfully with the manual entry on both Firefox and Chrome before making this change. As a regular follower of this group I do occasionally see people posting about not being able to file online. I think most of those are for other reasons (e.g., not having done an initial report in person, not being in the proper time window) but who knows, maybe this is causing problems for a few others as well so I thought it might be worth sharing my experience.